BR102020007717A2 - method for making an insulation board - Google Patents

Abstract

The invention relates to a method for manufacturing an insulating board (1) of predetermined width (B) comprising at least one covering layer (2) and a layer (3) of insulating material lying thereon, being that, the insulating material is produced by the fact that at least two components of a reactive mixture (4) are metered, mixed and led to a feed (5) of a distributor (6), and the reactive mixture (4) in the dispenser (6) is led along a flow path (7) to a number of nozzle openings (8) and is applied through the nozzle openings (8), whereby the reactive mixture (4) over the upper side (9) of the at least one covering layer (2) moving in a transport direction (F) with respect to the distributor (6).

Description

METHOD FOR MANUFACTURING AN INSULATION BOARD

[0001] The invention relates to a method for manufacturing an insulation board (insulation panel) with predetermined width, comprising at least one covering layer and a layer of insulating material (in particular, insulating foam) which is found on it, preferably, comprising two covering layers between which the insulating material layer is located, the insulating material being produced by the fact that at least two components of a reactive mixture are metered, mixed and led to a feed from a distributor; wherein, the reactive mixture in the dispenser is conducted along a flow path to a number of nozzle openings, and is applied through the nozzle openings, whereby the reactive mixture is applied onto the upper side of the at least one, covering layer moving in a transport direction relative to the dispenser, whereby the reactive mixture is applied through at least five nozzle openings, the reactive mixture from each nozzle opening being applied in the free stream on the upper side of the cover layer, the points of incidence of the jet in the reactive mixture on the cover layer are situated, in essence, in a line, which passes transverse to the direction of transport, and the distance of the two most extreme lateral incidence points it is at least 70% of the width.

[0002] A generic method is known from European patent document EP 2 051 818 B1. Similar solutions are shown by European patent document EP 1 857 248 B1, universal patent documents WO 2012/093129 A1, WO 2008/104492 A2 and American patent document US 2005/0222289 A1 .

[0003] Such a method is suitable, in particular, for the purpose of fabricating foam material connecting elements with flexible or rigid covering layers. Such connecting elements are used, in particular, for insulating purposes. In general, such connecting elements are produced on machines that work continuously. In this case, current production speeds reach up to 60 m/min. Typically such connecting elements are produced in widths of around 1,200 mm, for various applications, but widths from 600 mm to 1,500 mm are also possible.

[0004] The basic method for a continuous production of steel sandwich elements is described in German patent document DE 16 09 668 A1. In European patent document EP 1 516 720 B1 488 it is described that in addition to the metal covering layers, flexible covering layers such as, for example, paper or fleece materials can also be used. In the European patent document EP 1 857 248 B1 it is clarified that the previously usual oscillating order by means of a casting rake is limited with respect to the production speed. The oscillating order method is described in US patent document US 4 278 045 A.

[0005] Alternatively, in the mentioned European patent document EP 1 857 248 B1 a method is suggested, in which the reaction mixture is distributed through a distribution head to at least three output lines, the lines Flexible outlet pipes are fixed to a rigid frame transversely to the flow direction. The disadvantage of this method is that it is difficult to prevent the reaction mixture from sticking inside the tubes. In order to avoid this it has to be moved with a high air charge, which then also has to be generated no longer on the suction side of the metering pump, but on the pressure side, which is more expensive in machine technology. In the case of more reactive systems, but also despite the high air load, the method then hits its limits, as the cross sections of the tube narrow with time. This leads to high pressure losses. If adhesion does not start out exactly uniform across all tubes this leads to unequal amounts being distributed in the individual output lines. This in turn leads to internal stresses in the finished component, which during the cooling process lead to the finished connecting element bulging.

[0006] An alternative solution is represented by the casting rake. In this case, it is, in principle, a rigid tube, which is positioned, in essence, transverse to the direction of transport. This tube has a multitude of outlet openings through which the reaction mixture is applied. Various embodiments of foundry rakes of this type are described, for example, in the European patent document EP 2 051 818 B1, in the universal patent documents WO 2008/104492 A2 and WO 2012/093129 A1. A major problem with casting rakes of this type is the fact that in the case of these rakes with longer runtime starting with the outer holes adhesions of the reaction mixture occur. The residence time of the material inside the casting rake in outdoor areas is very long. Furthermore, there in general also the flow velocities are lower, since a corresponding adaptation of the flow cross section in order to avoid this effect leads to the fact that the total flow resistance for the material with the flow paths. shorter flow is so large, such that the distribution of quantities becomes uneven. Poor age distribution represents another problem, as the material with the longer flow paths leaving the casting rake is clearly older than the material with the shorter flow paths. Although there are several suggestions to address this problem with different measurements, the basic problem of a relatively long residence time and a relatively high specific surface within such casting rakes remains.

[0007] Problematic in the solutions mentioned above is the fact that at least parts of the reaction mixture in the mentioned solutions have relatively long flow paths, before the material is discharged into the atmosphere. Another disadvantage of these solutions is the fact that, with regard to flow, the solutions have a relatively large specific surface. Since the potentially sticky reactive reaction mixture can over time adhere to surfaces, it is advantageous to design discharge members in such a way that these organs have a specific surface with the smallest possible flow rate.

[0008] An advantageous solution regarding this is disclosed in fig. 5 of US patent document US 2005/0222289 A1 . This relatively simple solution with a central jet and two lateral jets, however, has the disadvantage that three branches lead to very pronounced confluence zones in the final product. In these confluence zones, a very irregular and disadvantageous cell orientation results, which is disadvantageous for the mechanical properties. Furthermore, in the case of only three branches, it is difficult to carry out the process, in such a way that during the confluence there will be no further inclusions of air, since in the case of only three branches it is difficult to avoid excessive rolling of the reaction mixture , after the material has reached the upper limit. Therefore, this solution does not work in the case of reactive systems with low start and rise times.

[0009] The solution of the problem represented in the mentioned US patent document US 2005/0222289 A1 by means of an application through several flat jet nozzles brings with it another problem: the relatively high thrust of the flat jets provides for the material to also flow contrary to the direction of transport. Since it is a flat jet pulled wide, the reaction mixture flowing in the opposite direction of transport has no possibility of deviating from the incident jet, as it passes this jet laterally. Instead the flat jet inevitably impinges on material flowing firstly in the opposite direction of transport, which is then dragged by the layer of deck moved in the direction of transport. In this case, a considerable impact of air bubbles occurs. Furthermore, it is almost impossible with a flat jet to obtain an even quantity distribution across the width. In this case, the indefinite quantity distribution, which is obtained with a flat jet (in particular, at the edges there is an accumulation of material, since the surface tension provides for the flat jet to contract externally) is more problematic in technology of the process than the defined distribution, which is obtained with individual but defined discrete branches. Therefore, in the case of flat jets it is actually more difficult to avoid inclusions of air under the upper covering layer.

[0010] Furthermore, in the case of the method suggested in the US patent document US 2005/0222289 A1, the same as in the case of the method described in the European patent document EP 1 857 248 B1 there is the disadvantage that due to the reactivity of the foam system it is difficult to avoid adhering material on the walls of the distribution system also in case of productions for several hours.

[0011] In this case, note that, preferably, very reactive systems could be used in order to avoid the effect of the so-called Ostwald maturation, in which in particular, at the end of the rise time smaller bubbles disappear in the foam, by the fact that they diffuse into adjacent larger bubbles. Thereby the insulating properties worsen. In the case of faster systems this process is restricted to a shorter time window, so smaller cell end products can be manufactured with faster systems with better insulating properties. The effect of Ostwald maturation is described in detail, for example, in European patent document EP 3 176 206 A1. In that publication the meaning of the fine cellular capacity of a foam structure in relation to insulating properties is also discussed.

[0012] In light of the various problems described above, it is the task of the present invention to further develop a generic process, in such a way that it is possible to uniformly apply the reaction mixture on the cover layer moving continuously, and, at the same time, it is also ensured that even in the case of long production runs and reactive systems, a reaction mixture can be reliably prevented from sticking to the distributor walls. The aim of the present invention is to apply the material in such a way that the age of the reactive mixture on an orthogonal imaginary plane is as homogeneous as possible in relation to the direction of transport. An inhomogeneous age distribution of the different branches leads to problems during the growth of the various branches and to non-homogeneous physical properties of the final product, which must be avoided according to the invention. In this case, a particularly critical effect is the fact that, due to internal stresses during cooling, the connecting elements bend and are no longer flat. Furthermore, it is intended to avoid or minimize the impact of bubbles during the application of the reactive mixture on the covering path.

[0013] The solution to this task is characterized by the invention in that the (average) age of the reactive mixture in each jet applied through the nozzle openings in the cut with a plane, which is perpendicular to the direction of transport, deviates around, in the maximum, 0.5 seconds of an arithmetic mean value across all jets, and the distributor has a specific flow surface, which has a value of at most 2.0 cm2/(cm3/s) (quotient between the surface that is in contact with the reactive mixture and the flow reactive mixture passing through the manifold).

[0014] The mixing of the components for the reactive mixture takes place first in a central mixing organ before it is transferred to the distributor feed. Through the openings in the nozzle, the reactive mixture manages to reach the atmosphere and manages to reach the free jet (thus according to the shape of a launching parabola) over the cover layer. In this case, the deck layer generally moves in the horizontal transport direction.

[0015] The choice of at least five openings of the mouthpiece has the advantageous consequence that also in the confluence zones a relatively defined cell orientation can be obtained. A cell orientation, in which the cells are also slightly extended vertically and especially in the area directly below the top covering layer, is desired as this positively results in the mechanical properties of the panel. In case of less than five branches, the individual branches are pressed out very strongly after the reactive mix has reached the upper limit. In that case, a chaotic and unfavorable cell orientation in the confluence zones then results. Furthermore, in the case of at least five branches it is easier to avoid excessive rolling of the material once the reactive mixture has reached the upper limit.

[0016] Advantageously, a clean tear-off corner is provided at the nozzle openings, so that no collar can form on the outlet side at the nozzle opening, which could disadvantageously influence the material trajectory. Advantageously in this dimension, it is preferably provided that there is a contour of the outer nozzle ending in a point (greater than 90°).

[0017] In addition, through the suggested execution form, it is obtained that also the corner or edge areas of the product to be manufactured clean are filled with reactive mixture.

[0018] After the points of incidence of the jet in the reactive mixture on the cover layer should be, in essence, on a line, with reference to this in particular, and preferably, it is provided that all points of incidence on the covering layer are situated in a section, which extends across a maximum of 200 mm, preferably across a maximum of 100 mm in the direction of transport. The points of incidence of the jets on the continuously moved deck layer are therefore located in the direction of transport, preferably within a corridor of at most 200 mm. This ensures a good age distribution. The operating parameters of the distributor (in particular, the flow rates and pressures of the reactive mixture) and its geometric shape (in particular, the position and alignment of the individual nozzles or nozzle openings in the distributor) are professionally made in order to carry out the procedure mentioned.

[0019] The reactive mixture in the dispenser is preferably guided from the feed to the nozzle openings through a maximum length of 150 mm. This form of execution has the advantage that less material adhesions to the walls in the distributor occur. In particular, in combination with high flow speeds this disadvantageous effect is further reduced. Heretofore it has been particularly and preferably foreseen that the (average) exit velocity of the reactive mixture out of the nozzle openings is between 1.5 m/s and 5.0 m/s. The aforementioned range has proven to be great, as speeds that are too low mean that the jets do not go far enough, or as a result the distributor has to be positioned too high. However, very high speeds lead to splashing during application.

[0020] Furthermore, it is preferably provided that the residence time (average) of the reactive mixture in the distributor is at most 0.15 seconds. A short residence time is very advantageous, in particular for reactive systems, in order to prevent adhesions to the distributor walls.

[0021] As the age of the mixture at a specific point so far, the time that elapses from the entry of the reactive mixture into the distributor feed until reaching the specific point must be understood. Therefore, the average age of the reactive mixture in the different branches, in an imaginary plane, deviates orthogonally from each other in relation to the transport direction by a maximum of 1 second. A favorable age distribution of this type is important so that no internal stresses arise in the finished component, which can lead to bulging in the component during cooling.

[0022] All jets of the reactive mixture in the (Q) direction transverse to the transport direction preferably arise, in essence, evenly spaced apart on the covering layer. In this particular case, it is foreseen that for all jets of the reactive mixture a tolerance range of 20% of the distance from the adjacent jet applies. For the points of incidence of the jets on the continuously moving road, transverse to the direction of transport, therefore, there are equidistant distances with a tolerance of at most +/-10%. An even distribution of this type for uniform growth of all branches is important once the material has reached the top deck layer. Otherwise it may be difficult to obtain a complete filling or a good density distribution. Uneven distribution can also lead to internal stresses during cooling, which then, in turn, can lead to a displacement of the finished plates (panel).

[0023] The two nozzle openings laterally more extreme spread the reactive mixture in two directions, which together form a plane, the two directions cut at an angle between 90° and 180°. At this point, therefore, the velocity vectors of the jets leaving the two most extreme nozzles are within vertically aligned planes, which form the aforementioned angle.

[0024] In the case of the specific flow surface provided according to the invention, it is the quotient between the surface that is in contact with the reactive mixture, and the flow reactive mixture that passes through the distributor. A small specific surface of this type, in turn, is very advantageous particularly for reactive systems, to prevent adhesions to the walls of the distributor.

[0025] Preferably, the width of the distributor in the direction (horizontal and) transverse to the direction of transport is at most 25% of the width of the insulation board to be manufactured, preferably at most 15% of that width.

[0026] In the case of the covering layer moving, the distributor is arranged, preferably, stationary.

[0027] The width of the insulation panel manufactured is typically around 1200 mm; for various applications, widths between 600 mm and 1,500 mm can also be envisaged.

[0028] The drawings show an example of the invention. They are shown:
In fig. 1 is a schematic perspective view of a distributor (i.e. a distribution member) with which the reactive mixture is applied over a covering layer in order to manufacture an insulation board (insulation panel),
In fig. 2, the cut through the dispenser with flow path designed for one of the nozzle openings,
In fig. 3, the top view of the distributor with the jets coming out of it of reactive mixture,
In fig. 4, the front view of the distributor and
In fig. 5, the side view of the dispenser.

[0029] In fig. 1 a system is schematically represented, with which an insulating panel 1 (insulation board as a foam material connecting element) is manufactured, in that a layer of insulating material 3 is applied to a covering layer 2 in the form of of a reactive polyurethane mixture 4. Insulating board 1 has a width B.

[0030] In this case, the covering layer 2 moves below a stationary arranged distributor 6, from which the reactive mixture 4 is applied, in a transport direction F with constant speed.

[0031] As is evident from the joint exposition with the other figures, the polyurethane reactive mixture 4 of the distributor 6 is applied in the form of a number of jets 10, that is, through openings of the nozzle 8 in the distributor 6 the reactive mixture 4 is sprayed in such a way that, as best seen in figure 1, it manages to arrive as a free jet and following the shape of a flight parabola on the deck layer 2, where it contacts at a corresponding number of incidence points 11 the upper side 9 of the covering layer 2.

[0032] In the execution example, eleven jets 10 are foreseen, whereby the number of jets 10 according to the invention is at least five; it has also been proven especially seven and nine jets 10. Furthermore, it is essential that the mentioned points of incidence 11 of the respective jet 10 in the reactive mixture 4 on the covering layer 2 are located, in essence, on a line 12, which passes through transverse to the direction of transport F, which is designated with Q. Furthermore, it is provided that the distance a (see figure 1) of the two laterally more extreme incidence points 11' and 11'' is at least 70% of the width B .

[0033] The circumstance that the jets 10 reach the deck layer 2, in essence, along the line 12 is specified by the fact that for the aforementioned points of incidence 11 it is foreseen that they lie within a section 13 (see Figure 1), which extends in the transport direction F, preferably through a maximum of 100 mm.

[0034] The width Bv (see figure 4) of the distributor 6, that is, its extension in the horizontal Q direction and transverse to the transport direction F (and with it also the width of the distributor section 6 equipped with nozzle openings 8) in that case it is preferably at most 25% of the width B of the insulating board to be manufactured, particularly preferably at most 15% of the width B.

[0035] The individual jets 10 must reach the surface 9 of the deck layer 2 in the Q direction as equidistant as possible. For this, in figure 1 it is illustrated that for the mentioned point of incidence 11 it is foreseen that, based on an equidistant distance of the individual jets 10, it must be in a tolerance band T, which is preferably at most 20% of the distance b from adjacent jet 10.

[0036] As a result, in the example execution, eleven jets 10 are applied by the distributor 6, which, moving continuously in the horizontal direction, manage to reach the covering layer 2, and then continue to be transported in the form of eleven branches.

[0037] Particularities of the distributor 6 can be inferred from the other figures 2 to 5.

[0038] In figure 2 is represented the cut through the distributor, and this cut passes exactly through the center of eleven flow paths 7 in total. As a result, the distributor 6 has a feed 5, through which it is fed with the reactive mixture 4 from a mixer not shown. The reactive mixture 4 is then transported along a flow path 7 to reach a nozzle opening 8, through which it is sprayed in the manner described as jet 10. In order to prevent adhesions the flow path is preferably not more than 150 mm in length.

[0039] From the top view according to Figure 3, it appears that the two most extreme nozzle openings 8' and 8'' are arranged in such a way that their spray direction forms the angle α, which is between 90° and 180°. The marked lines thus characterize the longitudinal axes of the two outer 8' and 8'' nozzles.

[0040] As, furthermore, it appears from the figures, the openings of the nozzle 8 spray the reactive mixture 4 in the transport direction F, therefore with the movement of the covering layer 2 that moves in the transport direction F with constant velocity under the distributor 6 arranged in a stationary manner.

[0041] As appears from figures 3 to 5 with respect to the arrangement and alignment of the individual nozzle openings 8, the individual nozzle openings or nozzles are arranged at very different angles to the horizontal. The outer openings of the mouthpiece are arranged at a markedly smaller angle to the horizontal. The professional form guarantees the above-mentioned goal, with given operating parameters, of placing the incidence points 11 next to each other in the transverse direction Q along line 12.

[0042] With the suggested execution form it is obtained that the reactive mixture 4 is finally applied on the covering layer 2 as a very homogeneous layer 3, in such a way that the quality of the insulating panel to be manufactured can be optimized.
List of reference numbers
1 insulation board (connecting element/foam material)
2 layer of cover
3 layer of insulating material
4 reactive mixture
5 distributor power supply
6 distributor
7 flow path
8 mouthpiece opening (nozzle)
8' mouthpiece opening (nozzle)
8'' mouthpiece opening (nozzle)
9 top side
10 jet
11 incidence point
11' incidence point
11'' point of incidence
12 line
13 section (tolerance range)
B width
F transport direction
Q direction transverse to direction of transport
T tolerance range
Bv distributor width
the distance of the two most extreme incidence points laterally
b distance from adjacent jet
α angle

Claims (10)

Method for manufacturing an insulating board (1) of predetermined width (B) comprising at least one covering layer (2) and a layer (3) of insulating material lying thereon, preferably comprising two layers of covered (2) between which is the layer (3) of insulating material, the insulating material being produced by the fact that at least two components of a reactive mixture (4) are metered, mixed and fed to a feed (5) of a dispenser (6), whereby the reactive mixture (4) in the dispenser (6) is conducted along a flow path (7) to a number of nozzle openings (8) and is applied through of the nozzle openings (8), whereby the reactive mixture (4) is applied on the upper side (9) of the at least one covering layer (2) moving in a transport direction (F) in relation to the distributor (6),
the reactive mixture being applied through at least five nozzle openings (8),
whereby, the reactive mixture from each opening of the nozzle (8) is applied in the free jet (10) on the upper side (9) of the covering layer (2),
the points of incidence (11) of the jet in the reactive mixture (4) on the covering layer (2) are located, in essence, in a line (12), which passes transverse (Q) to the direction of transport ( Faith
being that, the distance (a) of the two incident points (11', 11'') laterally more extreme is at least 70% of the width (B),
characterized by the fact that
the age of the reactive mixture (4) in each jet (10) applied through the nozzle openings (8) in the cut with a plane, which is perpendicular to the direction of transport (F) deviates around a maximum of 0.5 seconds of an arithmetic mean value across all jets (10), and the distributor (6) has a specific flow surface, which has a maximum value of 2.0 cm2/(cm3/s) (quotient between the surface that is in contact with the reactive mixture (4) and the reactive mixture (4) flowing through the distributor (6)). Method according to claim 1, characterized in that all incidence points (11) on the covering layer (2) are located in a section (13), which extends through a maximum of 200 mm, preferably through a maximum of 100 mm in the direction of transport (F). Method according to claim 1 or 2, characterized in that the reactive mixture in the distributor (6) is guided from the feed (5) to the nozzle openings (8) through a maximum length of 150 mm. Method according to one of claims 1 to 3, characterized in that the output velocity of the reactive mixture (4) out of the nozzle openings (8) is between 1.5 m/s and 5.0 m/ s. Method according to one of claims 1 to 4, characterized in that the residence time of the reactive mixture (4) in the distributor (6) is, at most, 0.15 seconds. Method according to one of claims 1 to 5, characterized in that all jets (10) of the reactive mixture (4) in the direction (Q) transverse to the direction of transport (F) are essentially spaced apart. evenly over the covering layer (2). Method according to claim 6, characterized in that for all jets (10) of the reactive mixture (4) a tolerance range (T) of 20% of the distance (b) of the adjacent jet (10) is valid. Method according to one of claims 1 to 7, characterized in that the two laterally more extreme openings of the nozzle (8', 8'') spread the reactive mixture (4) in two directions, which together form a plane, the two directions cut at an angle (α) between 90° and 180°. Method according to one of claims 1 to 8, characterized in that a distributor (6) is used, whose width (Bv, Bv) in the direction (Q) transverse to the direction of transport (F) is at most 25% of the width (B) of the insulation board (1) to be manufactured, preferably at most 15% of the width (B) of the insulation board (1). Method according to one of claims 1 to 9, characterized in that in the case of the covering layer (2) moving, the distributor (6) is stationary.

Images